This study was carried out to analyze the antifungal effect of essential oils from Monodora myristica (Gaertn) Dunal, Ocimum gratissimum L. and Zingiber officinalis (Roscoe) against Colletotrichum gloeosporioides (Penz.), the causal agent of anthracnose infecting mango fruits in Côte d'Ivoire. The inhibitory capacity of five concentrations (100, 200, 500, 1000 and 2000 ppm) of each essential oil were evaluated in vitro on the mycelial growth and spore germination of C. gloeosporioides. The efficacy of O. gratissimum oil on controlling postharvest anthracnose of kent mango fruit was evaluated both before and after inoculation using mycelia discs of C. gloeosporioides. The O. gratissimum oil inhibited completely (100%) the mycelial growth and spore germination of C. gloeosporioides at 1000 ppm in vitro. It is fungistatic at 1000 ppm and fungicide at 2000 ppm. The M. myristica oil showed the lowest inhibitory activity. The mango soaked into O. gratissimum oil concentration after inoculation yielded a highly protective effect against anthracnose disease in mango fruits at 1200 ppm. This treatment, presented the lowest infection rate (20%) and lesion size (0.22 ± 0.04 cm). Moreover, the four doses of O. gratissimum used, did not influence quality parameters of mango fruits. Therefore, essential oil of O. gratissimum could be an alternative to chemicals for control postharvest anthracnose of mangoes.

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Black Sigatoka, caused by the fungus Mycosphaerella fijiensis, is the main devastating banana (Musa sp.) leaf disease. The environmental and health constraints linked to the misuse of chemicals against this disease imply efficient methods aimed at reducing these products. This study, conducted on the Akressi site of Société Agricole Kablan Joublin (SAKJ), an industrial company of dessert banana, assessed the reduction in the dose of contact fungicide associated with adjuvants on black Sigatoka prevalence in Ivorian industrial banana tree plantations. This study made it possible to assess certain phytopathological (YLA, YNL and SI), growth (NEL and LER) and toxicity parameters of treatments every week over two months. Banana trees treated with reduced doses of VONDOZEB 62 OD associated with adjuvants induced statistically identical performance to the reference control. Thus, the use of reduced doses of fungicides associated with adjuvants appears to be an ideal strategy for reducing M. fijiensis severity and the use of chemical fungicides in the control of this disease.

The sugarcane smut disease caused by Sporisorium scitamineum occurs in all production areas. In order to contribute to the management of this disease, a study was carried out in vitro conditions. The aim of this study was to evaluate the antifungal efficacy and to determine the inhibitory concentration of the essentials oils of Ocimum gratissimum, Zingiber officinale and Cymbopogon citratus upon two strains B and Z of Sporisorium scitamineum. These oils were tested on mycelial growth of colonies, spores’ production and teliospores germination. The results showed a variable fungitoxic effect of the oils according to doses. Mycelial growth and spores production were totally inhibited (100%) from 1000 ppm by all the oils. The 90% inhibitory concentrations (IC90) obtained were 880.37 ppm, 847.83 ppm and 805.75 ppm for Ocimum gratissimum, Zingiber officinale and Cymbopogon citratus, respectively. The germination of teliospores was completely reduced by the three essential oils from 500 ppm upwards. Propiconazole had strong inhibitory effects at 400 ppm with a very low IC50 and the IC90 ranged from 305 ppm to 323.36 ppm. Moreover, at the level of the strains, no difference in resistance was observed These oils could provide a good means of controlling sugarcane smut.